The present invention relates to systems and devices for measuring arterial blood pressure. In particular, the invention relates to an improved method and device for measuring arterial blood pressure in a non-invasive manner using a transducer with an associated memory.
There has been a continuing need for devices which will measure blood pressure non-invasively, with accuracy comparable to invasive methods. Medwave, Inc. the assignee of the present invention, has developed non-invasive blood pressure measurement devices which are described in the following United States patents: U.S. Pat. No. 5,649,542 entitled CONTINUOUS NON-INVASIVE BLOOD PRESSURE MONITORING SYSTEM; U.S. Pat. No. 5,450,852 entitled CONTINUOUS NON-INVASIVE PRESSURE MONITORING SYSTEM; U.S. Pat. No. 5,640,964 entitled WRIST MOUNTED BLOOD PRESSURE SENSOR; U.S. Pat. No. 5,720,292 entitled BEAT ONSET DETECTOR; U.S. Pat. No. 5,738,103 entitled SEGMENTED ESTIMATION METHOD; U.S. Pat. No. 5,722,414 entitled CONTINUOUS NON-INVASIVE BLOOD PRESSURE MONITORING SYSTEM; U.S. Pat. No. 5,642,733 entitled BLOOD PRESSURE SENSOR LOCATOR; and U.S. Pat. No. 5,797,850 entitled METHOD AND APPARATUS FOR CALCULATING BLOOD PRESSURE OF AN ARTERY. Further description of these devices is found in U.S. patent application Ser. No. 08/912,139 filed Aug. 15, 1997, entitled HAND-HELD NON-INVASIVE BLOOD PRESSURE MEASUREMENT DEVICE, and U.S. patent application Ser. No. 09/299,222, filed Apr. 23, 1999, entitled BLOOD PRESSURE MEASUREMENT DEVICE WITH SENSOR LOCATOR.
As described in these patents and the pending patent applications, the Medwave non-invasive blood pressure measurement device and method determines blood pressure by sensing pressure waveform data derived from an artery. As varying pressure is applied to the artery by a sensing chamber, pressure waveforms are sensed by a transducer to produce sensed pressure waveform data. The varying pressure may be applied automatically in a predetermined pattern, or may be applied manually in a somewhat random fashion. The sensed pressure waveform data is analyzed to determine waveform parameters which relate to the shape of the sensed pressure waveforms. One or more blood pressure values are derived based upon the waveform parameters. The Medwave blood pressure measurement devices include both automated devices for continuously monitoring blood pressure (such as in a hospital setting) and hand-held devices which can be used by a physician, or by a patient when desired. These devices represent an important improvement in the field of non-invasive blood pressure measurement. Still further improvements, of course, are highly desirable.